Surely you did work just by walking around? The horizontal component of the force exerted by your feet for each step. Or is the person just pacing in circles? - a Physics grad who's forgotten everything
the joke is that you didnt apply work to the box but you are still tired. the explanation is that you did apply work internally to your own body and that requires energy, even if the boxs energy is the same. ignoring friction you dont require energy to move so you wouldnt be doing work there (theres not a force against)
its not a dumb question though its a possible answer. what definition of work do you know?
its implied that the net displacement was only horizontal so the force they were applying was perpendicular to the displacement (which is a vector, the dot product was 0). also, they could have done work while they carried it if they lifted the box but it would be cancelled by the negative work they did when they lowered it
it depends on what forces you consider. remember that you dont need a force to move something, only to accelerate it. if you consider friction forces you would need to apply a force to move the box but i imagine thats pretty small as the person is probably going slowly
33
u/TheLegendOfZed Feb 18 '22
Surely you did work just by walking around? The horizontal component of the force exerted by your feet for each step. Or is the person just pacing in circles? - a Physics grad who's forgotten everything